The Molecular Epidemiology Resource (MER) is a new shared research resource offering HCCC investigators support for high quality disease-specific outcomes research. The MER offers meticulous collection of longitudinal clinical data and biologic specimens including serum, plasma and germline DNA, all linkable to tumor samples catalogued in coordination with the Tissue Procurement Core. The HCCC strategic planning effort identified the importance of a robust infrastructure that facilitates linking molecular and clinical outcomes data. The MER is a critical component of this new infrastructure. Because the cost of such an effort is significant, the MER has focused its efforts on disease-specific groups that have the necessary clinical and research strength to utilize the resulting data. Current disease-specific groups supported by the MER include lymphoma, melanoma and sarcoma, myeloma, and cancers of the breast, pancreas, and GU. The MER is a rigorous, prospective observational database linked to a biorepository. All newly diagnosed patients with appropriate histologies as selected by the investigators are approached about informed consent. Following enrollment, MER personnel abstract clinical information including tumor stage, histology, lab and imaging data, treatment modality, treatment response, events (progression, death) and comorbidities. In general, clinical information on each subject is updated 2x/year for 3 years, then annually. Psychosocial data including quality-of-life analyses are collected longitudinally. Serum, plasma, buffy coat and peripheral blood DNA (at diagnosis and selected longitudinal time points) are collected, as is excess surgical tissue (tumor and normal) from resections and biopsies in collaboration with the Tissue Procurement Core. The clinical data are periodically validated to enable their readiness for analysis without investigators needing to return to the medical record. Over 5,000 subjects have been enrolled in the MER to date. In 2014, 35 investigators, of whom 26 were HCCC members were asking cancer questions in collaboration with HCCC members, utilized MER materials. Users came from each of the HCCC's four scientific programs. Data, biospecimens or both have been shared with 5 other NCI-designated cancer centers in the past year.